Transtibialalignment should allow for a relatively narrow, natural gait and should require as little energy as possible to achieve ambulation.Cosmetic finishing is also a factor when determining alignment as many prosthetic users desire a natural leg shape.

A prosthesis experiences downward forces from the residuallimb, in addition to the upward forces of the ground.If the socket and foot are not properly aligned, the socket can shift positions under force, and can hinder the user’s ambulation.

Observation of the prosthetic user while sitting is also required in order to ensure proper alignment.The user should be able to sit comfortably with at least 90 degrees of knee flexion, with both feet on the floor.

Amputees often underestimate the effect that shoe style has on prosthetic alignment.For example, switching to a higher shoe heel height without prosthetic alignment adjustment would result in too much dorsi flexion of the foot (the toe is too high up).In this case, the prosthetic user would feel as if he or she is falling forward.Conversely, switching to a lower shoe heel height without prosthetic adjustment would result in the toe being pointed too low, plantarflexion.In this case, the prosthetic user would feel as if he or she were falling forward.